Authors React Native E2E tests with Detox (Wix) - gray-box architecture (runs in-process with the app), `element(by.id|by.text|by.label)` matchers, `waitFor()` for explicit sync beyond Detox's automatic async tracking, Jest runner. Use when the app is React Native and speed matters. For Flutter use flutter-testing; for black-box cross-platform use appium-testing; for YAML-declarative flows use maestro-flows; for non-RN native use xcuitest-suite or espresso-suite.